Locking device for fluid-pressure tools



June 2, 1925. 1,540,374

r E. w. STEVENS LOCKING DEVICE FOR FLUID PRESSURE TOOLS Filed July 10, 9

INVEN TOR.

En'wafll W Slaverzs mmw A ATTORNEY.

Patented June 2, 1925.

UNITED STATES 1,540,374 PATENT OFFICE.

EDVJ'ARD W. STEVENS, OF DETROIT, MICHIGAN, 'ASSIGNOR 'IO CHICAGOPNEUMATIC TOOL COMPANY, OF NEW YORK, N. Y.. A CORPORATION OF NEW JERSEY.

LOOKING DEVICE FOR FLU'IIJ-PRESSURE TOOLS.

Application filed July 10, 1923. Serial No. 650,591.

To all whom it may concern.

- Be it known that I, EDWARD 7. STEVENS, a citizen of the United Statesof America, and resident of Detroit, in the county of Wayne and State ofMichigan, have invented new and useful Improvements in Locking Devicesfor F luid-Pressure Tools, of which the following is a specification.

This invention relates to locking devices for fluid pressure tools, suchas pneumatic percussive tools, and particularly to devices adaptedautomatically to maintain a tight connection between the cylinder andthe cylinder head or handle in spite of the jar and vibration caused bythe operation of the tool. One object of the invention is to provide asimple device of the class described which is" economical tomanufacture, easy to install, eliicient in operation and which is animprovement over prior devices of this character.

In order to illustrate the invention a preferred form thereof is shownin the accompanying drawing, in which: v

Figure 1 is a side elevational view partly in section of a pneumatichammer embodying the invention;

Figure 2 is a front elevational view of the locking ring with a portionof the cylinder in section showing the automatic take-up mechanism;

Figure 3 is a fragmentary plan view partly in section showing the partsin operative arrangement;

Figure at is a plan view of the preferred form of spring; and

Figure 5 is a view similar to Fig. 2 showing a modification.

The invention is illustrated in connection with a pneumatic hammerhaving a cylinder A, a cylinder head or cap B in threaded engagementwith the cylinder, a handle which may be integral with head B, athrottle control lever D pivoted to handle C, a deflector ring Ecovering the exhaust ports of the hammer and a locking ring F movableover the cylinder A and maintained in interlocked engagement with head Bby suitable means such as the spring clip (it. Any suitable interlockingmeans may be provided on the contacting faces of the head B and thelocking ring F such as cooperating ratchet teeth I) and f respectively.

The invention consists in the means proform of a lug a projecting intoan arcuate' recess it in locking ring F wherein the resilient membersuch as a spring 11 is housed to be compressed between the end wall ofrecess 7L and the lug a. While the lug 0; may be made integral with thecylinder,

as shown and by preference it is formed on a pin a. seated in a shallowbore a in cylinder A. In Figs. 1 to 4 inclusive, a flat type of spring7) is disclosed formed with reversed loops which requires only a veryshallow recess as indicated. In Fig. a modification of the invention isdisclosed in which a coil spring 2" is provided, the looking ring F inthis case being provided with a pronounced protuberance or extension topermit the formation of a recess h sufficiently deep to house thisspring.

The method of assembling the device is as follows: The cylinder head Bis threaded upon the hammer cylinder A and set up as tightly aspossible. Locking ring F is slipped over the cylinder until theabutments for the spring are in substantial alignment and spaced apartas far as recess h or it will permit. Spring 2' or c" is then insertedand the locking ring slid into engagement with the forward face of headit; A pipe wrench or spanner wrench is then used to rotate the lockingring against spring 2' pr 2" to compress the latter the desired amount,as two ratchet teeth. If ratchet teeth are not used for the interlockingmeans, the locking ring is backed off slightly during its partialrotation to compress the spring. With the parts in this position thespring clip G is applied and the tool is ready for operation. Duringoperation the jar and vibration in time may loosen the threadedconnection between cylinder A and cylinder head B, but the constantpressure exerted upon the ring F and interlocked head B by thecompressed spring 2' or 2" automatically takes up this looseness andmaintains a tight connection.

lVhile but one form and but one applica tion of this invention have beendisclosed Ill) herein, it is to be understood that the inventive idea isnot limited to the specific con struction or arrangement of parts shownbut includes all structural modifications or uses coming Withinthe scopeof the appendedclaims.

I claim:

l. in a pneumatic tool, in combination a cylinder and a cylinder head inthreaded engagement, a locking ring movable over said cylinder intocontact with: the said head, :1 lug on said. cylinder'eextend'ing'into arecess insaid ring, and means in said recess in en gagement with saidlug for rotating said head: relative: to said cylinderto take up anylooseness of said parts,

2. Ina pneumatic tool, in: combination a cylinder and a cylinderlieadin' threaded engapement, ring, movable over said cylinder into face,engagement with said head, interl' cking meansonsaid ring and head, saidring having a' recess, and means in said recess engaging said cylinderand said ring respectiyelyfor; rotating said head relatiye to saidcylinder to takevup looseness of said parts.

in a pneumatic tool,in combination a cylinder and a cylind'er head inthreaded engagement, a locking. ring encircling said cylinder andmaintained in iace engagement with said head, said ring having arecessadjacent said cylinder, alug on. said cylinder extending Within saidrecess, and a resilient member seated in said recess and adapted" to becompressedagainst said lug for constantly urging said: ring and saidhead in a direction to tighten tlie latter on said cylinder.

at. In a pneumatic tool, in combination, a cylinder and a cylinder headin threaded engagement, a ring encircling said cylinder and in contactwith said head, interlocking means on said head and said rin=g,and meansfor automa ticall y tightening said head on saidcylinder comprising aresilient member compressed between abutments on said cylinder and saidring respectively,

5. In a pneumatic tool, in combination, a cylinder and a cylinder headin threaded engagement, a ring encircling said cylinder and-in contactwith said head, interlocking means on said head and said ring, and meansfor automatically tightening said head on said cylinder comprisinga-butments on said cylinder and said ring disposed in the sametransverse plane and a spring compressed between said 'abutinents andseated in arecess in said ring.

6. In a pneumatic tool, incombination, a cylinder, a cylinder headinthreaded engagement therewith, a ring movable over said" cylinder andmaintained"v in interlocked engagement Withsaid head, and means forautomatically tightening said head on said cylinder comprising a pin on"said cylinder having a lug projecting into a recess in said ring and aspring housed in said recess and compressed between said lug and an endwall of said' recess.

7'. In a pneumatic tool, in combination, a cylinder, a cylinder head inthreaded engagement therewith, a ring movable over said cylinder andmaintained in interlocked engagement with said head, and means forautomatically ti'gl'itening said head on said cylinder comprising a pinon said cylinder havinga lug projecting into a recess in said ring and aflat reversely looped spring housed in said recess and compressedbetween said lug and an end Wall of'said recess.

Signed by me at Detroit, Michigan this 2nd day of July, 1923'.

EDWARD- W. STEVENS.

